Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum samples with indeterminate Western blot (WB) tests from 61 individuals whose sera were positive by enzyme-linked immunosorbent assay (ELISA) were studied in order to characterize their putative reactions with the human immunodeficiency virus (HIV) proteins and to resolve the HIV infection status of these individuals. The reaction observed by WB could not be confirmed either by radioimmunoprecipitation assay and subsequent electrophoresis (RIPA) or by use of LiaTek (Organon Teknika, Turnbout, The Netherlands) in 28% of the samples. Of the 86 samples that were indeterminate by WB, 66 reacted with p24 by WB; this reaction was confirmed by RIPA in only 21 (32%) and by LiaTek in 49 (74%) of the 66 samples. On the other hand, none of the indeterminate samples that reacted with HIV envelope proteins by WB did so by LiaTek, while 50% precipitated at least some of these proteins in the RIPA. The sensitivities of the three methods for detecting the antibody reaction with the different HIV proteins, which were studied with serial dilutions of positive serum samples, were similar. Thus, a lower sensitivity of RIPA or LiaTek does not seem to be the cause for the lack of reaction of the WB-indeterminate samples by these two methods. Sequential samples from individuals whose serum samples reacted by the three methods gave reproducible results, but all showed low antibody titers. Peripheral blood mononuclear cells obtained from three of the four individuals with sequential samples that reacted with HIV env proteins by WB and RIPA were negative for HIV provirus DNA after amplification by the polymerase chain reaction.
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PMID:Reactivity patterns and infection status of serum samples with indeterminate Western immunoblot tests for antibody to human immunodeficiency virus type 1. 157 66

Alternatives to confirmation of human immunodeficiency virus (HIV)-1 seropositivity by Western blot analysis were evaluated retrospectively using combinations of six anti-HIV-1 screening assays, including four enzyme-linked immunosorbent assays (ELISA) and two simple tests (a rapid dot immunoassay and an agglutination assay), according to an algorithm where sera are first screened by one assay and those repeatedly reactive on this assay are tested repeatedly by a second assay. Two panels of sera collected in Dar es Salaam, Tanzania, were used. Panel 1 was composed of 1,465 consecutive blood donor sera of which 99 (6.8%) were confirmed HIV-1 antibody positive, and panel 2 was composed of sera from 396 consecutively admitted patients at two medical wards of which 116 (29.3%) were confirmed HIV-1 antibody positive. Sera reactive on any of the six screening assays were also tested by a confirmatory Western blot assay. The sensitivity of the assays at the initial valid testing were as follows: Abbott 99.5%, Behring 99.5%, Organon 97.7%, Wellcozyme 100%, HIV CHEK-1 95.8%, and Serodia 95.8%. After repeat testing of sera that initially gave false-negative results all assays showed 100% sensitivity except HIV CHEK-1 (98.6%). The specificities after repeat testing were between 99.6 and 99.9% for all assays except for the Behring ELISA (98.1%). Several combinations of screening assays were found to give the same diagnostic accuracy as the screening assay followed by Western blot analysis. We conclude that an alternative confirmatory strategy can be fully satisfactory for some testing purposes.
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PMID:Alternative confirmatory strategies in HIV-1 antibody testing. 173 10

A new test, based on agglutination of gelatin particles (PA), sensitized with viral antigens of HIV, was applied on detection of the human immunodeficiency virus (HIV 1) antibody. Sensitivity compared to the ELISA tests (Organon, Dupond de Nemours and/or Elavia 2) was the same during the screening test (97.7 p. cent). Specificity was also acceptable when compared to the same tests (94 p. cent). This specificity remains acceptable with African sera (96 p. cent). During screening, 11.8 p. cent of tested sera were declared falsely positive by the Elisa classical techniques, against only 1.96 p. cent with the PA assay. The six sera remained positive with ELISA (false positives), whereas this positivity was not confirmed with the PA assay. Moreover, all the positive sera were confirmed with the Western blot HIV 1 assay (55.84 p. cent), HIV 1 + 2 (31.17 p. cent) or HIV 2 (13.0 p. cent). Amongst the five false positives pointed out in the european sera, all of them have shown in the Western blot the presence of one or two bands of the GAG protein. In this case, the assay whose easy use is attractive, can be adopted in screening serology and could be useful in African regions, as no further equipment is needed.
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PMID:[Statement: The evaluation of the Serodia-HIV and Serodia-ATLA FUJIREBIO-MILES kits]. 235 52

The pooling of individual serum samples to determine human immunodeficiency virus (HIV) seropositivity was examined to assess whether testing pooled sera was technically feasible, cost-effective, and accurate for estimating seroprevalence in large population surveys. The sensitivities and specificities of three commercially available HIV enzyme-linked immunosorbent assay (ELISA) kits were tested using 65 serum pools of 15 individual serum samples each (975 total serum samples) at two different dilutions. With pooled sera, the Organon Teknika Bio-EnzaBead ELISA at half the dilution recommended by the manufacturer showed the best agreement with ELISA and Western blot results of individual sera. In subsequently testing 92 pools, each containing 15 individual serum samples from a population of American patients attending a sexually transmitted diseases clinic, the estimated seroprevalence was 5.27 compared with 4.93% in a test of 1,380 individual serum samples and 5.19% in a test of 4,028 individual serum samples from the same population. In an evaluation of 1,380 African patients using 10 serum samples per pool, the estimated seroprevalence was 5.79 compared with 6.16% in a test of individual sera. These results indicate that ELISA testing with pooled sera is highly sensitive and specific and appears to be a cost-effective means for estimating HIV seroprevalence in large population-based surveys.
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PMID:Evaluation of human immunodeficiency virus seroprevalence in population surveys using pooled sera. 276 35

Six commercial enzyme immunoassays (EIA) were evaluated in 6488 serum samples, with immunoblot analysis as the confirmatory test for antibodies against human immunodeficiency virus (HIV). The Abbott and Wellcome tests identified all 163 immunoblot-positive samples correctly, whereas the other tests did not detect 1-3 samples. In AIDS patients (predominantly with antibodies to gp41env) Organon's EIA was less sensitive (p less than 0.05) and Wellcome's more sensitive (p less than 0.05) than the immunoblot assay. In symptom-free anti-HIV-positive subjects (antibodies to almost all viral antigens and high titres of anti-p24gag) all the EIA were significantly (p less than 0.05) less sensitive than the immunoblot assay. The frequencies of false-positive reactions in a "tricky" panel of samples from patients with autoimmune and acute viral diseases and in a blood-donor panel were Abbott 9.5%, 0.42%: Organon 1.7%, 0%; Litton 1.0%, 0.4%; Behring 2.7%, 0.06%; Wellcome 0%, 0%; and Pasteur 0%, 0.02%. The results of a seventh EIA (Dupont) were excluded from the study at the company's request. All six EIA evaluated are suitable tests for anti-HIV screening in samples from patients and blood donors.
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PMID:Evaluation of six enzyme immunoassays for antibody against human immunodeficiency virus. 287 39

Nine serial three-fold dilutions (1:1 to 1:6561) were prepared from 18 sera obtained from hemophiliacs confirmed to have antibodies to the human immunodeficiency virus. The dilutions were tested with five different commercial enzyme immunoassay kits and twelve sera were retested 5 to 7 months later by different lots of three kits. The dilution that gave an absorbance (OD) equal to the cut-off OD was considered as the titer of antibody. Sensitivities of the kits were compared by statistical and regression analysis; the same approach was used for studying reproducibility from the results of retesting. The highest titers were found with the Wellcome kit, the lowest with Organon and Pasteur kits, whereas intermediate values were found with the Sorin/Biomedica and Electronucleonics kits. With the Organon and Wellcome kits, excellent reproducibility was observed on later retesting; however, a significant change in titers was seen on retesting the Sorin kit.
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PMID:Studies of the sensitivity and reproducibility of commercial kits to detect antibodies to the human immunodeficiency virus. 302 6

Anti-human immunodeficiency virus enzyme-linked immunosorbent assay kits marketed by Electro-Nucleonics Inc. (ENI), Genetic Systems Corp. (GSC), Organon Teknika Inc. (OTI), Ortho Diagnostic Systems Inc. (ODSI), and Wellcome Diagnostics (WD) were evaluated by using 289 randomly selected serum samples from a high-risk population and 53 serum samples likely to produce false-positive results. The radioimmunoprecipitation assay was used as the reference test. Sensitivities ranged from 96.51% (ODSI, WD) to 97.67% (ENI, GSC, OTI). Sera showing antibodies to viral glycoproteins only produced the false-negative results. Specificities ranged from 99.6% (ENI, GSC, ODSI, OTI) to 100% (WD). False-positive results were obtained with sera from patients with autoimmune disease or Epstein-Barr virus infection. Only results from GSC and OTI kits were distributed in two compact clusters well segregated on either side of the cutoff point. ODSI and GSC kits had the best intralot reproducibility. The GSC kit had the best interlot reproducibility. Cutoff values for ODSI and GSC kits were the least variable. Intraplate repeatability was good for all kits. Sample localization was not an important source of variability. Our results do not point out one outstanding kit among the five evaluated. However, the GSC kit showed the best overall results.
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PMID:Performance and reliability of five commercial enzyme-linked immunosorbent assay kits in screening for anti-human immunodeficiency virus antibody in high-risk subjects. 317 Jul 12

51 human sera containing antibodies to human immunodeficiency virus 1 (= HIV-1) were examined for HIV-1-antigen by three different enzyme immunoassay procedures (= EIA) of Abbott, Organon and Dupont. Sensibilities, handling as well as the correlation with the clinical stages of HIV-infection were compared. The EIA's diagnosed in accordance 6 sera which contained HIV-1-antigen and 42 sera to be HIV-1-antigen negative. 3 sera showed differences: according to the EIA of Organon none of these sera contained HIV-1-antigen, the EIA of Abbott (but not of Dupont) analysed HIV-1-antigen in one of these sera, in the other two sera only the EIA of Dupont showed HIV-1-Antigen. It is concluded that the differences in these 3 serum samples may originate not only in the different types of EIA used (indirect/direct procedure) but also in the different capture antibodies provided (antibodies against p-24 antigen or polyvalent antibodies).
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PMID:[Detection of HIV-1 antigen--determination using 3 different test systems]. 328 30

The second-generation enzyme immunoassays (EIAs) for antibodies against human immunodeficiency virus (HIV) from three manufacturers (Abbott, Organon, Wellcome) and three anti-HIV confirmatory tests, i.e. Western Blot (WB, Biotech, Dupont), radioimmunoprecipitation assay (RIPA, CLB) and a competitive immunoassay (CIA, Abbott) were evaluated on a panel of 6,488 serum samples, which had previously been used for the comparison of seven first-generation EIAs. For the present study the panel was expanded with sequential serum samples from 12 individuals followed at 1- to 3-month intervals during seroconversion for anti-HIV. The second-generation EIAs and confirmatory tests were significantly more sensitive than the first-generation EIAs as was demonstrated by detection of 10- to 100-fold higher endpoint titers in anti-HIV-positive sera as well as by earlier detection of anti-HIV in 7-11 of the 12 subjects, who seroconverted. In all sera obtained during early HIV infection anti-gp 160/120env antibodies (WB, CIA) were found in addition to anti-p24 (WB, RIPA) and in serial twofold dilutions of these 'seroconversion samples' the new Abbott EIA and RIPA were significantly more sensitive than WB (p less than 0.05), whereas CIA and the new Organon EIA were significantly less sensitive than WB (p less than 0.05). The new Wellcome EIA was not statistically less sensitive than WB. The CIA was as sensitive as WB for antibodies to envelope proteins (gp41, gp160, gp120), but considerably less sensitive for core (p24) antibodies, as was shown in sera obtained during early as well as later clinical stages of HIV infection.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Evaluation of three second-generation and three confirmatory assays for antibodies to human immunodeficiency virus. 328 66

We have compared the Karpas AIDS Cell Test for antibodies to the human immunodeficiency viruses (HIV) with a commercial enzyme-linked immunosorbent assay (ELISA) (Organon Teknika) by testing serum samples from 324 intravenous drug abusers in Turin. The cell test was found to be more sensitive and as specific as the ELISA with the serum samples from the drug abusers. In Lisbon, 30 samples were tested on slides containing cells infected with HIV-1 and/or HIV-2. All 15 samples, which were positive for HIV-2 alone (in the HIV-2 Elavia test and by the Western blotting technique), were also positive in the Karpas AIDS test. In contrast, only one of the 15 samples (7%) gave a positive reading in the ELISA for HIV-1. Results of 30 samples tested in Turin and Lisbon by the Western blotting technique agreed closely with those obtained with the Karpas AIDS Cell Test. We were also able to show that the entire test can be performed at room temperature and completed within 1 hour. Moreover, the cell test requires minimal skill and simple equipment and is inexpensive. It also includes non-infected cells as a control and the specificity of positive samples may be verified with a bench microscope. Furthermore, this test which detects antibodies to both HIV-1 and HIV-2 allows rapid typing of the infecting strain.
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PMID:The Karpas AIDS Cell Test compared with an enzyme-linked immunosorbent assay for detecting antibody to the human immunodeficiency viruses (HIV-I and HIV-2). 329 99


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